Generator regulation



Dec. 5, 1933. c. STANSBURY GENERATOR REGULATION Filed Feb. 2, 1931 $ww/wM/v @Mmm WWW; 8o f Mmww Patented Dec. 5, 1933 UNITED STATES PATENT OFFICE GENERATOR REGULATION poration of Delaware Application February 2, 1931. Serial No. 512,927

9 Claims.

' This invention relates to voltage or current regulation by means of electron tubes.

An object of the invention is to accurately regulate the voltage of a generator.

Another object is to control the electrical input of a translating device which may be supplied from a source or variable voltage or current.-

Other objects and advantages will hereinafter appear.

The accompanying drawing illustrates diagrammatically one embodiment of the invention, it being understood that the system illustrated may be modified in various ways without departing from the scope of the appended claims.-

Referring to the drawing L and L are respectively the positive and negative supply lines of a direct current circuit.. 1 is the armature of a direct or alternating current generator and 2 is its field winding.which is to be controlled to maintain the armature voltage constant. 3

.and 4 are two thermionic gaseous tubes having respectively cathodes 3' and 48', anodes 3 and 4 and grids 3 and 4. The cathodes 3 and 4 may be activated in any well known manner. A vibratory relay 5 has its exciting winding 5 connected across the terminals of the generator armature 1. The relay is equipped with a pivoted armature 5 which is biased by an adjustable spring fi the purpose of the adjustment being to regulate the voltage at which the relay responds. The armature is equipped with normally closed contacts 5 and normally open contacts 5. A potentiometerresistance 6 is connected between the grid 4 and the line L while its adjustable tap is connected to the stationary contact of the pair 5. A second potentiometer resistance .7 is connected between the grid 3 and the line L while its adjustable tap is connected to the stationary contact of the pair 5. The movable contacts 5? and 5 are electrically connected. through the relay armature to line L The anode 4 is connected through a resistance 8 to the line L the cathode 4 being connected to line L. The field winding 2 has one terminal connected to the line L while its other terminal is connected to the anode 3 the cathode 3 being connected to the line L A condenser 9 is connected between the anodes 3 and 4 A second condenser 10 is connected between the anode 4 and the grid 3, while a third condenser 11 is connected between the anode 3 and the grid-4. An adjustable resistance 12 is connected in shunt with the tube 3.

The apparatus functions in the following manner:

Initially the grids 3 and 4 have the potentials vance of the other.

of their respective cathodes and are therefore incapable of stopping the current flow through the tubes 3 and 4 when the lines are first energized. Upon energization of the lines the potential dii ference between them is impressed upon the .tubes 50 3 and 4. A relatively small current flows from line L through winding 2 and resistance 12 to line L and the generator is thus excited at a low value. Due to slight diflerences in the voltage necessary to start passage of current through the 5; tubes and the difierences in the impedances of their respective circuits, the initial wave im-' pressed upon the main electrodes of the two tubes will initiate current flow through one tube in ad- As the impedance 8 in series with tube 4 is considerably less than the impedance 2 in series with the tube 3, current will probably first flow through tube '4. The instantaneous voltage at which the discharge starts is somewhat above the voltage drop between the anode and cathode after current flow is established. Hence as soon as tube 4 carries current, the potential of anode 4 and with it that of condenser plate 9*, is lowered, causing a corresponding drop of the potential of plate 9 and anode 3 with the 30 result that the voltage between cathode 3" and anode 3 is too low to permit the start of adischarge through tube 3. After some time the potential of plate 9 and with it that of anode 3 reaches that of line L whereupon the tube 3 be- 35 comes conducting. This causes the potential oi. the plate 9 to be reduced, causing a corresponding reduction of the potential of plate 9 and of anode 4 to a value which stops the flow of current through the tube 4. As the tube 3 becomes .conducting it'shunts the resistance 12, thereby increasing the current flow through the field winding 2 and tending to raise the voltage oi. the generator.

The sudden flow of current through the tube 3 also changes the potential of condenser plate 11, which previously was that of line L to a lower value, resulting in a corresponding drop to a negative value of the potential of plate 11* and grid 4. Aslong as grid 4 is negative with respect to its cathode 4 current through tube 4 cannot be re-established. The charge of condenser 11, however, gradually leaks oil through the resistance 6, line L. tube 3 to plate 11*. As soon as tube 4 has again become conducting through the discharge of the negative potential on grid 4, it will again pass a current and by action similar to the aforedescribed stop the flow of current through tube 3 and subject the grid 3 to a transient negative potential due to the chargdesired, be supplied directly'by the armature.

'tions of the generator.

- or alternating current type.

ing' of the condenser 10. Thus the tubes alternately become conducting and the intermittent passage of current through tube 3 varies the current of the exciting field 2, the average current depending upon the relative times during which the tubes 3 and 4 are conducting, as well as upon the value of the resistance 12.

If the voltage of the generator tends to rise above a certain value, which depends upon the adjustment of the spring 5, the relay opens contacts 5 and closes contacts 5 This increases the resistance 7 in the discharge circuit of condenser 10 and decreases resistance 6 in the discharge circuit of condenser 11. As a result the tube 4 will become conducting for a relatively longer interval and tube 3 for a relatively shorter interval, so that the average currentthrough winding 2 is reduced and the tendency of the generator voltage to rise is checked.

It. is, of course, possible to so design and adjust the relay 5 that the contacts 5 and 5 are open simultaneously which will result in astill more sensitive response of the system to voltage varia- In actual operation the relay constantly vibrates and thereby constantly varies the duration of the alternate intervals of the current variations resulting from the alternate operation of the two tubes.

The system provides for further adjustment by regulation of the resistance 12 and it is also possible to make the resistances 6 and 7 so that their total value may be varied by manual adjustment.

The generator illustrated may be of the direct In the former case the exciting current for the field winding may, if

Furthermore, the condensers 9, 10 and 11 may be made variableand the relay armature may be caused to produce by mechanical movement variations in the capacity of the condensers 10 and 11' to thereby vary the discharge period of the respective circuits and thus regulate the operation of the tubes.

While the drawing shows the relay coil 5? connected across the armature of the generator, so as to be responsive to its voltage, it is obvious that the system may be employed for regulating the armature current, in which case the relay coil 5 is connected m series with'the armature in manner well known in the art.

Other modifications coming within the scope of this disclosure and the appended claims readily suggest themselves to one skilled in the art.

What I claim as new and desire to secure by Letters Patent is:

1. In combination, a generator having a field winding supplied with direct current, a gaseous discharge tube in circuit with said winding and having an anode and a grid, means to impress transient potentials upon said anode and grid to stop the discharge current of the tube, said means 2. In combination, a generator having a field winding supplied with direct current, a gaseous discharge tube in circuit with said winding and having an anode and a grid, means to impress transient potentials upon said anode and grid to stop the discharge current of the tube, said means including an adjustable energy storage circuit associated with the grid and responsive to an operating characteristic of the generator whereby the rate of discharge of the transient potential on the fiuence of an operating characteristic of said armature whereby the rate of discharge of the transient grid potential is varied in accordance with said operating condition. 4. In combination, a generator havinga field winding supplied with direct current, a gaseous discharge tube in circuit with said winding and having an anode and a grid, means to impress transient potentials upon said anode and grid to stop the discharge current of the tube, a regulable energy storage circuit connected to said grid, and means responsive to an operating characteristic of the generator and adapted to regulate said energy storage circuit to thereby vary the rate of discharge of the transient potential on the grid in accordance with said operating condition.

5. In combination, a generator having a field winding supplied with direct current, a gaseous discharge tube in circuit with said winding 'andhaving an anode and a grid, means to impress transient potentials upon said anode and grid to stop the discharge current of the tube, a regulable energy storage circuit connected to said grid, a relay connected to said generator and responsive to one of its operating characteristics and adapted to regulate said energy storage circuit to thereby discharge tube in circuit with said winding and having an anode and a grid, a second tube normally non-conducting, when said first tube is conducting, means to cause said second tube to conduct current whereby transient potentials are produced on said anode and grid which stop the flow and having an anode and a grid, a second tube normally non-conducting, when said first tube is conducting, means to cause said second tube to conduct current whereby transient potentials are produced on said anode and grid which stop the flow of current through the first tube, a regulable energy storage circuit connected to said grid, and a relay connected to said generator and responsive to one of its operating characteristics and adapted, to regulate said energy storage circuit to thereby control its rate of discharge in response to said operating condition. y

8. In combination, a generator having a field winding supplied with direct current, a gaseous discharge tube in circuit with the fieldwinding and having an anode and a grid, a second tube having an anode and a grid, means associated with each tube to produce transientv potentials .upon the anode and grid of the other tube to stop the flow of current therethrough, regulable energy storage circuits associated with the grids, and means responsive to an operating characteristic of said generator and adapted to regulate said energy storage circuits to thereby control the time intervals during which the grids maintain their respective tubes non-conducting in accordance with said operating condition.

9. In combination, a generator having a field winding supplied with direct current, a gaseous 

